[POWERPC] Add function to check if address is an IO port

This adds a function that tells you if a given kernel virtual address
is hitting a PCI or ISA IO port permanent mapping or not. This is to
be used in the next patch to fix iomap APIs to properly unmap things.

Signed-off-by: Benjamin Herrenschmidt <[e-mail]>
Signed-off-by: Paul Mackerras <[e-mail]>

arch/powerpc/kernel/pci-common.c

···
 		kfree(phb);
 }
 
+int pcibios_vaddr_is_ioport(void __iomem *address)
+{
+	int ret = 0;
+	struct pci_controller *hose;
+	unsigned long size;
+
+	spin_lock(&hose_spinlock);
+	list_for_each_entry(hose, &hose_list, list_node) {
+#ifdef CONFIG_PPC64
+		size = hose->pci_io_size;
+#else
+		size = hose->io_resource.end - hose->io_resource.start + 1;
+#endif
+		if (address >= hose->io_base_virt &&
+		    address < (hose->io_base_virt + size)) {
+			ret = 1;
+			break;
+		}
+	}
+	spin_unlock(&hose_spinlock);
+	return ret;
+}
+
 /*
  * Return the domain number for this bus.
  */

include/asm-powerpc/pci-bridge.h

···
 	return bus->sysdata;
 }
 
+static inline int isa_vaddr_is_ioport(void __iomem *address)
+{
+	/* No specific ISA handling on ppc32 at this stage, it
+	 * all goes through PCI
+	 */
+	return 0;
+}
+
 /* These are used for config access before all the PCI probing
    has been done. */
 int early_read_config_byte(struct pci_controller *hose, int bus, int dev_fn,
···
 
 extern void isa_bridge_find_early(struct pci_controller *hose);
 
+static inline int isa_vaddr_is_ioport(void __iomem *address)
+{
+	/* Check if address hits the reserved legacy IO range */
+	unsigned long ea = (unsigned long)address;
+	return ea >= ISA_IO_BASE && ea < ISA_IO_END;
+}
+
 extern int pcibios_unmap_io_space(struct pci_bus *bus);
 extern int pcibios_map_io_space(struct pci_bus *bus);
 
···
 pcibios_alloc_controller(struct device_node *dev);
 #ifdef CONFIG_PCI
 extern unsigned long pci_address_to_pio(phys_addr_t address);
+extern int pcibios_vaddr_is_ioport(void __iomem *address);
 #else
 static inline unsigned long pci_address_to_pio(phys_addr_t address)
 {
 	return (unsigned long)-1;
+}
+static inline int pcibios_vaddr_is_ioport(void __iomem *address)
+{
+	return 0;
 }
 #endif